Screen.



No 781,493 l PATENTEDJAN. s1

J. ,GLEMB'NTS & G. KNOWLING.

SCREEN. v

PPLIoATIoN FILED JUNE 6. 1.904.

sums-santi' 1.. l

No. 781,493. i

" J. GLEMBNTS & G. fxNowlLlNa.

` SGRBEN. l APRLIOATION FILED .TUNEIGl 1904.

PATENTED JAN. 31,1905..

I UNITED STATES Patntea January s1, 1905.

PATENT.l OFFICE.

SCREEN.

SPECIFICATION forming part of Letters Patent No. 781,493, dated January31, 1905.

Application iiled June 6, 1904. Serial No. 211,382. l

To (LZZ whom t may concern,.-

Be it known that we, JAMES CLEMENTS and GEORGE KNowLING, subjects of theKing of Great Britain, residing at Goat Wharf, Brentford, county ofMiddlesex, England, have invented a certain new and useful Improvementin Screens, of which the following is a speciiication. f

This invention relates to a screen for screening coal, gravel, sand,iiour, grain, and other powdered or granular materials.

The important feature of our improved screen is the provision of aseriesof transverse horizontal bars or wires arranged in a frame adapted to beinclined at any desired angle in combination with a plain orunperforated surface on which the material to be screened is caused tofall or is thrown and from which said material slides over the barsaforesaid. Inv so sliding the material is. screened to a grade dependingon the inclination of the frame. The bars or wires are usually loose intheir supports and are free to rotate, whereby they keep themselves clean.

Referring to the accompanying drawings, which illustrate our invention,Figure 1 is a front View of the screen. l Fig. Q'is a longitudinalsection thereof on the line m Fig. l. Fig. 3 is a side view, drawn to alarger scale, of Aa portion of one side of the frame, showing thebearing .for the wires or bars. Fig. L is a section on the liney y, Fig.8. Fig. 5 is a front view of a modified form of screen.

' Fig. 6 is a longitudinalcentral section of said 1 or supports B, bywhich it can be set and supported at any desired inclination.

C C are rods or wires extending transversely across the frame from sideto side and forming the screen proper.

D is a plain or unperforated surface immediately above the wires orrods, on which surface the materials to be screened are allowed to fallor are thrown. Said materials then slide down said plain surface andover the wires or rods, and the finer particles thereof pass through thescreen, while the coarser particles fall down in front of the screen andcollect at the foot thereof. .The effective width of the openingsbetween the wires or rods can be varied by changing the inclination ofthe frame. The'greater the angle the less is the 'effective width andthe less the angle the greater is the effective. width, so that bytilting the frame more or less the character of the screening can bevaried. We provide theframe with side wings E and in some cases with atop wing F, and preferably the wires or rods do not extend to the bottomof the frame, a plain part Gr being provided partly to separate thescreened heap of materials from the coarser materials and partly toassist in holding the sides of the f frame together.

The wires or rods C are in most cases not held tight in their bearings,but are quite slack, as shown in Figs. 3 and 4. By this arrangement, therods can move about and rotate, and in this way the accumulation on themofthe material being screened is prevented. We may provide rods or wiresof circular ortriangular or other section. A triangular-shaped rod isvery advantageous in that it facilitates the lrotation thereof and thethrowing of the material to be screened from one rod to the next. Thebearings of the wires or rods are formed by holes J in bearing-plates K,secured to the sides of the frame A. For large screens it may benecessary to support the transverse wires or rods by one or morelongitudinal bearing-bars. In Fig. 5 we have shown one such bearing-barL, extending down the center of the frame. The holes M,- Fig. 6, in thebar L, through which the wires pass, are elongated, so that the wirescan move about, as above described.

ln some cases we provide the screen with a hopper N, Figs. 5 and 6, atits upper end, into which the materials to be screened are thrown andfrom which said materials fall onto the plain surface D of the screen.The outlet of said hopper is shown furnished with a hinged iiap P,controlled by a handle Q, and notched quadrant R, by which the openingcan be varied as desired, i f

For screeningvery fine materials where fine wires are necessary thewires are very liable to bend unless held tight. In such cases they arenot allowed to shake about` but are secured at their ends and preferablyare tightened by moving their intermediate bearings S longitudinally tobend the Wires, as indicated in Fig. 7

What We claim isl. The combination of a frame having perforations at thesides elongated in the direction ofthe plane of the frame to receivetransverse Wires or rods loosely mounted therein and movable in theirown plane, said Wires or rods, and a plain surface above and in the sameplane as said Wires or rods, substantially as described.

2. In combination, a frame having holes JAMES (ELEMENTS. GEORGE KNOVVLIN (Jr.

Witnesses:

JOHN T. KNoWLEs, ALEXANDER W. ALLEN.

